AFR 190 heads limit?

[clutchdust]

I picked up a used set of AFR 190 heads about a year ago for a really good deal. So as time and money permit I am working on putting them in my car. They were complete assemblies but I don't believe in just slapping on any used part, so I've disassembled them and had them checked just to make sure they're not cracked. Now I'm cleaning them up a little. They don't really have much to go but I'm just knocking down any casting flash and polishing the bowls as much as possible.
So anyway, the cam I have now is the Comp Cams Xtreme Energy 276 listed at 276 intake/282 exhaust. Lift is advertised at .502 and .510 with a 1.5 rocker. Before I reassemble these heads I'm planning on upgrading the springs a bit and switching to a 1.6 rocker to support the additional lift. The lift should put me in the .530-.540 range.
Since I really don't know the history of these heads I'm going to change the springs and seals anyway. My question revolves around capacity. I've heard these heads run out of steam at about .500" lift anyway. So even if that's true, is there a down side to switching to the 1.6 rockers and increasing that lift?
For what it's worth, the engine is a 90's truck roller block, +.030" with hyper pistons with a 3.5cc dome, should net me around 9.5-10:1SCR.

 

[enkeivette]

You need more compression to take full advantage of those, mill them. And no, they will make more power with more lift. The 190s don't cap out at .5 I'm sure.

 

[AJ77]

Gary, if those are the heads you got from me, the guy I bought them from said they were already milled. You might need to check if you can go any farther without any issues with alignmemt--bolt holes, manifold, etc. Art

 

[clutchdust]

Yes, they're the same ones, Art. I know they're milled. I don't plan on milling them any more. If I need to change CR, I will do what I can with gaskets.

 

[JAKE]

AFR 190s definitely don't run out of breath at .500" valve lift. Not the 190s.

There's some controversy about their 180s though and I believe that's based on the flow chart AFR posted on their site/in that catalog, etc.

Who told you that, BTW? An AFR hater?

Jake

 

[clutchdust]

I don't remember who told me that. I saw it on one of these forums somewhere. One of those smart ass comments like, "Oh those heads are junk. They run out of breath at .500. Should just go buy some CNC milled 225 heads and while your at it get a Donovan block and Callies crank and some good forged SRP pistons... and don't forget the poly valve covers, they're worth like 5 more horsepower, blah, blah, blah."

PS, congratulations Jake and Ryan. Semper Fi

 

[JAKE]

I don't remember who told me that. I saw it on one of these forums somewhere. One of those smart ass comments like, "Oh those heads are junk. They run out of breath at .500. Should just go buy some CNC milled 225 heads and while your at it get a Donovan block and Callies crank and some good forged SRP pistons... and don't forget the poly valve covers, they're worth like 5 more horsepower, blah, blah, blah."PS, congratulations Jake and Ryan. Semper Fi

LOL, Yea, that's about how it goes. Some just LOVE to spend other folk's money. I even coined a term for it "PILING ON". You ask about changing spark plugs and they end up having you spend a thousand dollars.

Thanks for the congrats; I'll pass it along to Ryan.

Jake